Latches for vehicle hoods and the like are typically actuated in two stages. During a first stage a handle is actuated inside the vehicle which moves the latch from a primary closed position to secondary closed position. To release the latch completely the vehicle occupant typically can either exit the vehicle and actuate a lever that is under the hood or can activate the handle during a second stage (e.g. double pull) from inside of the vehicle to move the patch from the secondary closed position to the open position.
In terms of lifting a hood in general and specifically for an active pedestrian protection system, the latch is needed to provide a travel that is greater than (e.g. over travel of the striker within the slot of the latch) that which is used for normal opening. Due to mechanical limitations of springs and targets for mass and packaging, the normal opening lift of the hood cannot be as high as compared to what is provided using the active pedestrian protection system. There is a need for automatic reset of the latch when an over slam condition is encountered due to a pedestrian impact with the hood. There is also a need for normal operation of the same latch (e.g. outside of an over slam condition) where the extra travel is not utilized.
The automotive industry is attempting to better protect pedestrians from head on collisions with vehicles. When a car hits a pedestrian in a front collision, the pedestrian can be thrown up and land on the front hood of the vehicle and/or the windshield. In an effort to ameliorate the harshness of the impact, and in particular to prevent the person's head from hitting the engine block or other hard point located directly underneath the front hood, it is desired to actively space the front hood from the engine block whenever a front end collision is detected.